I want to go to either Disney world,universal,or Busch Gardens while staying in miami with my aunt,which one?

I'm currently staying with my aunt who lives in Coral Gables, FL and I'm probably gonna be here for 2 more months, but I really wanna go to either Disney world, Universal Studios, or Busch gardens. It's just gonna be me and my boyfriend and we have $700 available to spend. I'm wondering which is best to go to for our budget? BTW we have acar to drive there.